Indoor Solar Clothes Dryer

This idea is for a low energy clothes dryer that's to be built as part of one's home -- although it wouldn't take much extra work to make it a separate building, if you wanted to do that.

First, choose/design a room on the south side of the house. Insulate that room thoroughly, on the exterior wall, in the ceiling and floors, and on the walls between this room and the rest of the house.

Incorporate into the interior walls, ceiling, and floor (but not the exterior wall) a vapor barrier, to prevent humidity from moving between this room and the other rooms of the house.

Add to the exterior wall a passive solar space heater, and a small heat recovery ventilator (HRV). *Don't* use an energy recovery ventilator -- that would be silly.

To avoid the need to run an electrical fan to blow air through the HRV, one can optionally design the system so that air makes the following circuit: Fresh (dry) air enters through the HRV (located in the wall near the room's floor), passes through the solar air heater, then enters the room near the ceiling. Stale (humid) air from near the floor of the room passes through the HRV, then up a chimney. Because no HRV is 100% energy efficient, the air coming out of it will inevitably be warmer (and less dense) than ambient air; thus, the stack effect will draw the air up the chimney.

Add clotheslines, and an insulated air tight door. The door can either lead into the house (ideally, into whatever room the washing machine is in), or out of the house (though I can't think why one would want that).